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(note: this is a temporary file, to be added-to by anybody, and moved to
release-notes at release time)
+
+Transaction fee changes
+=======================
+
+This release automatically estimates how high a transaction fee (or how
+high a priority) transactions require to be confirmed quickly. The default
+settings will create transactions that confirm quickly; see the new
+'txconfirmtarget' setting to control the tradeoff between fees and
+confirmation times.
+
+Prior releases used hard-coded fees (and priorities), and would
+sometimes create transactions that took a very long time to confirm.
+
+
+New Command Line Options
+========================
+
+-txconfirmtarget=n : create transactions that have enough fees (or priority)
+so they are likely to confirm within n blocks (default: 1). This setting
+is over-ridden by the -paytxfee option.
+
+New RPC methods
+===============
+
+Fee/Priority estimation
+-----------------------
+
+estimatefee nblocks : Returns approximate fee-per-1,000-bytes needed for
+a transaction to be confirmed within nblocks. Returns -1 if not enough
+transactions have been observed to compute a good estimate.
+
+estimatepriority nblocks : Returns approximate priority needed for
+a zero-fee transaction to confirm within nblocks. Returns -1 if not
+enough free transactions have been observed to compute a good
+estimate.
+
+Statistics used to estimate fees and priorities are saved in the
+data directory in the 'fee_estimates.dat' file just before
+program shutdown, and are read in at startup.
+
+Double-Spend Relay and Alerts
+=============================
+VERY IMPORTANT: *It has never been safe, and remains unsafe, to rely*
+*on unconfirmed transactions.*
+
+Relay
+-----
+When an attempt is seen on the network to spend the same unspent funds
+more than once, it is no longer ignored. Instead, it is broadcast, to
+serve as an alert. This broadcast is subject to protections against
+denial-of-service attacks.
+
+Wallets and other bitcoin services should alert their users to
+double-spends that affect them. Merchants and other users may have
+enough time to withhold goods or services when payment becomes
+uncertain, until confirmation.
+
+Bitcoin Core Wallet Alerts
+--------------------------
+The Bitcoin Core wallet now makes respend attempts visible in several
+ways.
+
+If you are online, and a respend affecting one of your wallet
+transactions is seen, a notification is immediately issued to the
+command registered with `-respendnotify=<cmd>`. Additionally, if
+using the GUI:
+ - An alert box is immediately displayed.
+ - The affected wallet transaction is highlighted in red until it is
+ confirmed (and it may never be confirmed).
+
+A `respendsobserved` array is added to `gettransaction`, `listtransactions`,
+and `listsinceblock` RPC results.
+
+Warning
+-------
+*If you rely on an unconfirmed transaction, these change do VERY*
+*LITTLE to protect you from a malicious double-spend, because:*
+
+ - You may learn about the respend too late to avoid doing whatever
+ you were being paid for
+ - Using other relay rules, a double-spender can craft his crime to
+ resist broadcast
+ - Miners can choose which conflicting spend to confirm, and some
+ miners may not confirm the first acceptable spend they see
+